The big thing that I found seriously lacking with Pinterest is that they just haven't figured out a way to source the current URL of a page that the browser is on. As of this writing, you have to manually put it into a field in the code for the button to return a visitor to the page. Lame to the extreme; especially if you have any more than a few pages to deal with. In the case of WP, the number of pages will always continue to grow at a pretty fast rate. Either that, or I totally missed a Really Big Thing somewhere in their docs. Is there a way to do this similar to Facebook and Twitter?